Cartridge ejection mechanisms and methods for operating the same

ABSTRACT

Cartridge ejection mechanisms and methods of operating the same are disclosed. An illustrated example cartridge ejection mechanism includes a bolt head which has a front face to close a cartridge chamber, a first longitudinal cross-piece on a first side and a second longitudinal cross-piece on a second side. The first and second cross-pieces extend from the front face of the bolt head toward the rear of the bolt head. The cartridge ejection mechanism also includes at least two cartridge extractor hooks spring-mounted to the bolt head in opposed, facing relation to jointly extract a cartridge or cartridge case from the cartridge chamber when the bolt head moves rearward. Additionally, the cartridge ejection mechanism is provided with a stationary ejector assigned to one of the cartridge extractor hooks and having two projection disposed adjacent a corresponding one of the cross-pieces of the bolt head such that, when the bolt head moves sufficiently rearward, the cartridge or cartridge case strikes the projections, pivots around the cartridge extractor hook opposite the ejector, and is ejected to the side opposite the ejector.

RELATED APPLICATION

This patent arises from a U.S. patent application which is (a) acontinuation of International Patent Application Serial No.PCT/EP2003/009492, filed Aug. 27, 2003, (b) a continuation ofInternational Patent Application Serial No. PCT/EP2003/009483, filedAug. 27, 2003, and (c) a continuation-in-part of U.S. patent applicationSer. No. 10/956,562, filed on Oct. 1, 2004. U.S. patent application Ser.No. 10/956,562 is a continuation of International Patent ApplicationSerial Number PCT/EP03/09490, which was filed on Aug. 27, 2003.International Patent Application Serial No. PCT/EP2003/009492,International Patent Application Serial No. PCT/EP2003/009483,International Patent Application Serial Number PCT/EP03/09490, and U.S.patent application Ser. No. 10/956,562 are all hereby incorporatedherein by reference in the entirety.

FIELD OF THE DISCLOSURE

This disclosure relates generally to handheld firearms, and moreparticularly, to cartridge ejection mechanisms and methods of operatingthe same.

BACKGROUND

Throughout this patent, position designations such as “above,” “below,”“top” “forward,” “rear,” etc. are referenced to a firearm held in anormal firing position (i.e., pointed away from the shooter in agenerally horizontal direction).

As far as can be inferred from the figures of U.S. Pat. No. 3,906,651,the '651 Patent appears to illustrate a cartridge with a round profile.The cartridge is seated on the breech block of a breech that has twoopposing extractor hooks. The reason why this ejection arrangement hasbeen chosen cannot be inferred from this publication, nor is it possibleto infer from this publication how the ejector should be arranged andconstructed. The profile of the two extractor hooks is also unusual andfacilitates sliding from the cartridge border. Such sliding must bepossible in the case of one of the hooks, if it is not intended to beuncommonly softly cushioned. However, a longitudinal groove in thebreech which is located close to one of the hooks and could hold theejector may be recognized in FIG. 2 of this publication.

The ejection of some shotgun cartridges, (for example, of the 10 or 12caliber), is often a problem, particularly in the case of very longcartridge cases and in semi-automatic weapons. Because the rapidlyopening breech of a semi-automatic weapon carries the extractor hookswith it, cartridges having a round border profile may slip from theextractor hooks during this rapid opening movement.

Doubling the amount of extractor hooks as known from U.S. Pat. No.3,906,651 could possibly remedy this problem. Further, having double theamount of extractor hooks could be advantageous in the case of extremelylarge cartridges which have a disproportionately small border (e.g.,flare, tear gas or shotgun cartridges of the 4 caliber (26.5 mm), 4 cmshell cartridges, or the like.).

In former times, small arms, particularly in the case of serviceweapons, were all constructed for right-handed marksman. Left-handerswere, thus, trained to use the weapon with their right hand. Today,however, there is an attempt to do justice to the characteristics of themarksman by, for example, equipping weapons for use by left-handers.Particularly in the case of semi-automatic rifles of the Bullpup stylewherein the magazine is located behind the butt, equipping the rifle foruse by a left-handed marksman requires ensuring that cartridge ejectionis directed away from the face of the marksman, since the ejector istypically located at the level of the cheekbone.

In the case of some weapons, (for example, with aircraft machine gunsmounted in helicopters), the direction of ejection is not freelyadjustable, but must instead be adapted to the mounting conditions asbest as possible. Under such circumstances, it may be desirable to causethe cartridge ejection to take place in any direction, except at thereloading mechanism. For example, if a cartridge gripper seated abovethe weapon is used, then the ejection can take place to the right or tothe left, or even below, depending on where a cartridge case containeror spent ammunition bag can be mounted.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a top perspective view of an example breech of asemi-automatic shotgun.

FIG. 2 is a top view of the breech and ejector of FIG. 1.

FIG. 3 is an enlarged view of an example extractor hook.

FIG. 4 is a partial view of an example ejector, seen from the front orthe rear.

DETAILED DESCRIPTION

FIGS. 1-4 illustrate an example ejector mechanism for an example breechof an example semi-automatic firearm. The example weapon of FIG. 1includes a bolt head (1) which can be moved along two guide rods (3).This bolt head (1) includes a breech block (5). An extractor hook (7) ismounted on each side of the bolt head (1).

An example extractor hook (7) is shown enlarged in FIG. 3. The extractorhook (7) may be, for example, stamped out of sheet metal. Theillustrated extractor hook (7) has a somewhat T-shaped profile. The endof the middle jamb of the extractor hook (7) defines a bore hole (9). Arear leg (11) of the extractor hook (7) and a front leg (13) of theextractor hook (7) extend in opposite directions from the middle jamb.Each of the rear leg (11) and the front leg (13) is positioned at aright angle to the middle jamb.

The rear leg (11) of the extractor hook (7) includes an angularconnecting piece (15) on its free end. This connecting piece (15)engages in a spiral pressure spring (not shown). The front leg (13) ofthe extractor hook (7) includes a hook (17) on its free end. The hook(17) has a surface (19) turned toward the middle jamb. The surface (19)defines an acute angle, a, with respect to an axis (88) that runsparallel to the middle jamb of the extractor hook (7) and transverse tothe breech block (5) (FIG. 2). Each of the extractor hooks (7) can bepivoted about a substantially vertical axis. Each of these pivot axes isdefined by a retaining pin (21) which passes through the bore hole (9)of the corresponding extractor hook (7) (see FIGS. 1 and 2).

Each side of the bolt head (1) includes a longitudinal cross-piece (25).A corresponding one of the extractor hooks (7) is mounted on each ofthese cross-pieces (25). Each longitudinal cross-piece (25) has an upperand a lower edge. The upper and lower edges extend into the breech block(5) (i.e., to the front face of the bolt head (1)).

FIG. 2 is a top view of the breech of FIG. 1. In the example of FIG. 2,the two extractor hooks (7) are seated on opposite sides of a cartridge(23). An ejector (27) is located behind the bolt head (1). When viewedfrom the front or from the rear as in FIG. 4, the ejector (27) has aU-shaped cross-section. When the bolt head (1) moves towards the back, acorresponding one of the longitudinal cross-pieces (25) runs through theejector (27). The legs (29) of the ejector (27) engage the upper andlower surfaces of the corresponding longitudinal cross-piece (25) andextend onto the bolt head (1).

The cartridge or cartridge case (23) is held on the bolt head (1) by theextractor hooks (7). Thus, the cartridge or cartridge case (23) iscarried along with the bolt head (1) when the bolt head (1) movesrearward. The ejector (27) remains stationary during this movement ofthe bolt head (1). Consequently, the longitudinal cross-piece (25) movesthrough the two legs (29) of the ejector (27) as the bolt head (1) movesto the rear. As the breech block (5) passes the ejector (27), the baseof the cartridge (23) runs into the ends of the legs (29) of the ejector(27) and is pressed against the extractor hook (7) adjacent the ejector(27). Due to the interaction of the round profile of the cartridgeborder with the beveled edge (19) (FIG. 3), the extractor hook (7) ispressed back and the ejector (27) imparts a powerful thrust to theadjacent part of the cartridge border, so that the cartridge (23) tiltsaround the extractor (7) on the side opposite the ejector (27) and isejected.

Switching the ejector (27) to the opposite side of the breech from thatshown in FIG. 2 causes a similar ejection to the right.

The ejector (27) can be inserted into a longitudinal or transverse slotin the case of the weapon. A component of the weapon or a pin may holdthe ejector (27) in this position.

As will be appreciated by persons of ordinary skill in the art, theabove-described ejector mechanism is suited for use with a smallfirearm, (e.g., a semi-automatic weapon), which includes a barrel and abreech that moves approximately from the rear end of the barrel to therear along the axis of the bore (i.e., along the median axis of thebarrel) when opening. The example cartridge ejection arrangementdescribed above includes extractor hooks (7) and an ejector (27). Theextractor hooks (7) grasp the border or near the border of the cartridgeor engage in the peripheral groove of its base. The ejector (27) isseated approximately opposite one of the extractor hooks (7) in relationto the axis of the bore. The ejector (27) is positioned so that theborder of the cartridge base runs into it as the bolt head (1) movesrearward. In the illustrated example, the ejector (27) is stationary.Thus, the ejector (27) may be either rigidly mounted to the weapon orits case. Alternatively, the ejector (27) may be flexibly mounted in thebreech or the bolt head (1) to, at the end of the return motion of thebreech, run into a weapons-proof resistor.

In the illustrated example, the cartridge or cartridge case is ejectedtransverse to the axis of the bore. The extractor hooks (7) are onopposite sides of the axis of the bore. The ejector (27) is located onthe side of the axis of the bore opposite to the side to which thecartridge is to be ejected.

In the case of cartridges with a border groove which is turned towardthe breech block (i.e., toward the front surface of the breech (5)), thecartridge border forms an even surface (i.e., is flush) with the frontsurface of the breech (5). During ejection, the extractor hooks (7) aresnugly seated in the grooves with a complementary supporting surface.Therefore, the cartridge or its case cannot be released from theextractor hooks (7) until a transverse force is applied to the case. Inthis way, a reliable ejection of the cartridge case is ensured. In thecase of a cartridge border with a round profile, (for example, in thecase of small arm and shotgun cartridges), the engagement between thecartridge case and the extractor hooks (7) is only a frictionalconnection. A powerful spring is, thus, employed to stress the extractorhooks (7) toward the cartridge case in order to ensure the cartridgecase remains captured between the hooks (7) during withdrawal and, thus,to ensure reliable ejection.

From the foregoing, persons of ordinary skill in the art will appreciatethat improved cartridge ejection arrangements have been disclosed.Further, the ejection arrangements illustrated above enable the ejectiondirection to be changed to suit the marksman or situation presented bythe intended use of the weapon.

For instance, in the disclosed examples, a stationary ejector (27) isassigned to one or both of the cartridge extractor hooks (7) such that,when the breech or bolt head (1) moves rearward, the cartridge orcartridge case is extracted from the cartridge chamber by all of thecartridge extractor hooks (7). Subsequently, the base of the cartridgestrikes the stationary ejector (27), pivots around the cartridgeextractor hook (7), and, in the process, is ejected to the side of thefirearm opposite the ejector (27).

It is assumed that each of the extractor hooks (7) has only a limitedcapacity for keeping the cartridge (23) or cartridge case in theposition in which it is pulled out. The use of several extractor hooks(7) is beneficial, particularly with problematic cartridges such asthose mentioned above. If an ejector (27) may be assigned to any of theextractor hooks (7), except for those on whose side the ejection is totake place, then the ejection can take place in any desired direction.

Persons of ordinary skill in the art will appreciate that the possiblenumber of extractor hooks (7) is limited by practical considerationssuch as weight and cost. Typically, three or more extractor hooks willonly be practical for cartridges with very large diameters. In keepingwith these considerations, the examples illustrated above include onlytwo opposed cartridge extractor hooks (7) and one movable ejector (27).This approach is sufficient for Bullpup weapons.

If the ejector (27) includes two ejector projections arranged onopposite sides of one of the two cartridge extractor hooks (7) and whichrun in longitudinal grooves of the breech or bolt head (1) that are inopen communication with the front face of the bolt head (1) on bothsides of the cartridge extractor hook (7), then an ejection arrangementis created, which extracts even difficult cartridges and cartridgecases. This arrangement can be converted with the simplest of resourcesfrom right to left ejection and vice versa. In particular, to convertthe ejection arrangement from right to left ejection or vice versa, onlythe ejector projections need be moved. The locations of the breech andthe extractor hooks (7) remain unchanged.

Conventional cartridge extractor hooks have hooked shaped ends withsurfaces turned toward the breech block to engage a cartridge border.Unlike these prior art extractor hooks, the extractor hooks (7)disclosed herein have ends with surfaces that form an acute anglerelative to a plane parallel to the front face (5) of the bolt head (1)such that the surfaces are angled out from the breech block (5) towardthe front of the weapon. Preferably, this acute angle ranges between 0°and 15°.

In the above mentioned U.S. Pat. No. 3,906,651, the extractor hooks aredesigned to complement the profile of the cartridge border with whichthey are to be used. In contrast, in the disclosed example in which thesurface of the extractor hooks (7) form acute angles relative to a planeparallel to the front face (5) of the bolt head (1), cartridges ofwidely varying styles may be used (e.g., a cartridge (23) whose borderis parallel to the front surface (5) of the bolt head (1) or a cartridgehaving a border which is turned away from the front surface (5) of thebolt head (1) (e.g., flare cartridges)) Such cartridge cases aremanufactured by turning on a lathe or by indirect extrusion.

Persons of ordinary skill in the art will appreciate that the abovedisclosed arrangements may be used for all kinds of small arms. It isparticularly advantageous to employ these arrangements with largecaliber cartridges. For example, it is especially preferred to employthe illustrated arrangements with a repeating or semi-automatic shotgun. In such circumstances, the structural diversity and mutualdeviation between cartridges of the same caliber is particularly great.On the other hand, the need for retrofitting a weapon for left-handedand right-handed marksmen is also particularly great. Such a weapon istypically not a personal weapon like an automatic rifle, which canaccompany a soldier during practically his entire period of duty, butrather is often only given out for special operations.

Example cartridge extraction and ejection assemblies are described inU.S. patent application Ser. No. ______ (Attorney Docket No.20020/10047), which has been incorporated herein in its entirety byreference. Example breech mechanisms are disclosed in U.S. patentapplication Ser. No. ______ (Attorney Docket No. 20020/10047) and inU.S. application Ser. No. ______ (Attorney Docket No. 20020/10055),which is hereby incorporated herein in its entirety by reference.

Although certain example methods, apparatus and articles of manufacturehave been described herein, the scope of coverage of this patent coversall methods, apparatus and articles of manufacture fairly falling withinthe scope of the appended claims either literally or under the doctrineof equivalents.

1. A cartridge ejection mechanism comprising: a bolt head having a frontface to close a cartridge chamber, a first longitudinal cross-piece on afirst side of the bolt head and a second longitudinal cross-piece on asecond side of the bolt head, the first and second cross-piecesextending from the front face of the bolt head toward the rear of thebolt head; at least two cartridge extractor hooks spring-mounted to thebolt head in opposed, facing relation to jointly extract a cartridge orcartridge case from the cartridge chamber when the bolt head movesrearward; and a stationary ejector assigned to one of the cartridgeextractor hooks and having two projection disposed adjacent acorresponding one of the cross-pieces of the bolt head such that, whenthe bolt head moves sufficiently rearward, the cartridge or cartridgecase strikes the projections, pivots around the cartridge extractor hookopposite the ejector, and is ejected to the side opposite the ejector.2. A cartridge ejection mechanism as defined in claim 1, wherein atleast one of the cartridge extractor hooks includes a hook-like endhaving a surface facing the front face of the bolt head, the surface ofthe hook-like end being disposed at an acute angle to a plane parallelto the front face of the bolt head.,
 3. A cartridge ejection mechanismas defined in claim 2, wherein the acute angle is between approximately0° and approximately 15°.
 4. A cartridge ejection mechanism as definedin claim 1, wherein the cartridge ejection mechanism is structured toextract a cartridge or cartridge case having a caliber of at least 15mm.
 5. A cartridge ejection mechanism comprising: a bolt head having afront face to close a cartridge chamber, first and second longitudinalgrooves on a first side of the bolt head and a third and fourthlongitudinal grooves on a second side of the bolt head, the longitudinalgrooves extending from the front face of the bolt head toward the rearof the bolt head; at least two cartridge extractor hooks spring-mountedto the bolt head in opposed, facing relation to jointly extract acartridge or cartridge case from the cartridge chamber when the bolthead moves rearward; and a stationary ejector assigned to one of thecartridge extractor hooks and having two projection disposed incorresponding ones of the grooves of the bolt head such that, when thebolt head moves sufficiently rearward, the cartridge or cartridge casestrikes the projections, pivots around the cartridge extractor hookopposite the ejector, and is ejected to the side opposite the ejector.6. A cartridge ejection mechanism as defined in claim 5, wherein atleast one of the cartridge extractor hooks includes a hook-like endhaving a surface facing the front face of the bolt head, the surface ofthe hook-like end being disposed at an acute angle to a plane parallelto the front face of the bolt head.,
 7. A cartridge ejection mechanismas defined in claim 2, wherein the acute angle is between approximately0° and approximately 15°.
 8. A cartridge ejection mechanism as definedin Claim l, wherein the cartridge ejection mechanism is structured toextract a cartridge or cartridge case having a caliber of at least 15mm.
 9. A method of ejecting a cartridge comprising: grasping a rear edgeof a cartridge or cartridge case with at least two cartridge extractorhooks spring-mounted to a bolt head in opposed, facing relation;carrying the cartridge or cartridge case rearward with the bolt head;and striking the cartridge or cartridge case on two projections of astationary ejector assigned to one of the cartridge extractor hooks topivot the cartridge or cartridge case around the cartridge extractorhook opposite the ejector and eject the cartridge or cartridge case tothe side opposite the ejector.